diff --git a/nvx-rs/src/host/sandbox/mount.rs b/nvx-rs/src/host/sandbox/mount.rs
index c90e30184..5ec97f304 100644
--- a/nvx-rs/src/host/sandbox/mount.rs
+++ b/nvx-rs/src/host/sandbox/mount.rs
@@ -77,14 +77,12 @@ impl MountAccess {
     ///
     /// Fails with [`ErrorKind::Unsupported`](crate::ErrorKind::Unsupported) for another name.
     pub fn from_name(name: &str) -> Result<Self> {
-        match name {
-            "ro" => Ok(Self::ReadOnly),
-            "rw" => Ok(Self::ReadWrite),
-            _ => Err(refused(format!(
-                "unsupported sandbox mount mode {}; choose ro or rw",
-                repr(name)
-            ))),
-        }
+        setting_from_name(
+            "mode",
+            [Self::ReadOnly, Self::ReadWrite],
+            Self::as_str,
+            name,
+        )
     }
 }
 
@@ -117,14 +115,7 @@ impl MountOwner {
     ///
     /// Fails with [`ErrorKind::Unsupported`](crate::ErrorKind::Unsupported) for another name.
     pub fn from_name(name: &str) -> Result<Self> {
-        match name {
-            "vmm" => Ok(Self::Vmm),
-            "caller" => Ok(Self::Caller),
-            _ => Err(refused(format!(
-                "unsupported sandbox mount owner {}; choose vmm or caller",
-                repr(name)
-            ))),
-        }
+        setting_from_name("owner", [Self::Vmm, Self::Caller], Self::as_str, name)
     }
 }
 
@@ -157,14 +148,7 @@ impl MountKind {
     ///
     /// Fails with [`ErrorKind::Unsupported`](crate::ErrorKind::Unsupported) for another name.
     pub fn from_name(name: &str) -> Result<Self> {
-        match name {
-            "directory" => Ok(Self::Directory),
-            "file" => Ok(Self::File),
-            _ => Err(refused(format!(
-                "unsupported sandbox mount kind {}; choose directory or file",
-                repr(name)
-            ))),
-        }
+        setting_from_name("kind", [Self::Directory, Self::File], Self::as_str, name)
     }
 }
 
@@ -174,6 +158,29 @@ impl fmt::Display for MountKind {
     }
 }
 
+/// Returns the one of `values`, the two values of a share's `setting`, whose name, as `as_str`
+/// gives it, is `name`, as a recorded share gives it.
+///
+/// Fails with [`ErrorKind::Unsupported`](crate::ErrorKind::Unsupported) for another name, with a
+/// message that names the setting and its two values.
+fn setting_from_name<T: Copy>(
+    setting: &str,
+    values: [T; 2],
+    as_str: fn(T) -> &'static str,
+    name: &str,
+) -> Result<T> {
+    values
+        .into_iter()
+        .find(|&value| as_str(value) == name)
+        .ok_or_else(|| {
+            let [first, second] = values.map(as_str);
+            refused(format!(
+                "unsupported sandbox mount {setting} {}; choose {first} or {second}",
+                repr(name)
+            ))
+        })
+}
+
 /// A kind of access-policy path.
 #[derive(Clone, Copy, Debug, PartialEq, Eq, Hash)]
 pub enum PolicyKind {